Coated chitosan nanoparticles encapsulating caspase 3 activator for effective treatment of colorectral cancer.

Cancer is the second leading cause of death worldwide, the deaths are projected to continue rising, with an estimated 12 million deaths in 2030. The aim of the present investigation is to prepare and compare the uncoated (U-CH NP) and eudragit S 100-coated (E-U-CH NP) chitosan nanoparticles encapsulating a caspase 3 activator (UCN 01), by ionic gelation method. The prepared formulations were studied for various parameters like particles size, zeta potential, transmission electron microscopy, atomic force microscopy, in vitro release study, ex vivo study using Caco 2 colon cancer cell line, and in vivo studies. The particle size and zeta potential of developed formulation was found to be particle size of 168 ± 3.7 nm and +35.8 ± 3.7 for U-CH NP and 265 ± 4.1 nm and +22.3 ± 1.1 for E-U-CH NP. TEM and AFM images revealed that U-CH NPs were round in shape and smoother at surface as compared to E-U-CH NP which have irregular surface due to coating. The E-U-CH NP showed better in vitro release than uncoated formulation in SCF (pH 6.8) than in SGF (pH 1.2). The cytotoxicity was performed by MTT assay. U-CH NP showed enhanced cytotoxicity as compared to blank (without drug) formulation. There was an increase in caspase 3 activity of U-CH NP as compared to UCN 01 alone. E-U-CH NP showed better tumor regression ability than U-CH NP. The results of plasma profile and tumor regression study demonstrated that E-U-CH NP has continuous release profile of UCN 01 and comprehensive residence time. Thus, it is better acceptable than free UCN 01 and may be a potential delivery system for the targeting and treatment of colon cancer.

Mannosylated chitosan nanoparticles for delivery of antisense oligonucleotides for macrophage targeting.

The therapeutic potential of antisense oligonucleotides (ASODN) is primarily dependent upon its safe and efficient delivery to specific cells overcoming degradation and maximizing cellular uptake in vivo. The present study focuses on designing mannosylated low molecular weight (LMW) chitosan nanoconstructs for safe ODNs delivery by macrophage targeting. Mannose groups were coupled with LMW chitosan and characterized spectroscopically. Mannosylated chitosan ODN nanoparticles (MCHODN NPs) were formulated by self-assembled method using various N/P ratio (moles of amine groups of MCH to phosphate moieties of ODNs) and characterized for gel retardation assay, physicochemical characteristics, cytotoxicity and transfection efficiency, and antisense assay. Complete complexation of MCH/ODN was achieved at charge ratio of 1:1 and above. On increasing the N/P ratio of MCH/ODN, particle size of the NPs decreased whereas zeta potential (ZV) increased. MCHODN NPs displayed much higher transfection efficiency into Raw 264.7 cells (bears mannose receptors) than Hela cells and no significant toxicity was observed at all MCH concentrations. Antisense assay revealed that reduction in lipopolysaccharide (LPS) induced serum TNF-α is due to antisense activity of TJU-2755 ODN (sequence complementary to 3'-UTR of TNF-α). These results suggest that MCHODN NPs are acceptable choice to improve transfection efficiency in vitro and in vivo.

Treatment of cutaneous candidiasis through fluconazole encapsulated cubosomes.

Cubosomes encapsulating fluconazole were prepared by emulsification method and characterized for particle size, entrapment efficiency, SEM, in vitro release, skin irritation studies, and confocal laser scanning microscopy. The cubosomes prepared were 257.2 ± 2.94 nm in size and with drug entrapment efficiency of 66.2 ± 2.69 %. The prepared formulation was characterized for surface morphology by SEM analysis which revealed their smooth surface. The cumulative percentage of fluconazole from cubosomes permeated via dialysis membrane (molecular weight cutoff (MWCO) 12-14 kD) showed 76.86 % cumulative drug release, while fluconazole solution showed release up to 91.04 % in 24 h in phosphate-buffered saline (PBS) (pH 6.5), and sustained release is obtained after 24 h in case of cubosomes. The animal studies also revealed that the cubosomes are non-irritant and have sustained antifungal activity.

Edible transgenic plant vaccines for different diseases.

Edible plant vaccines are immunogenic preparations containing antigenic proteins rather than pathogens, therefore, they sanctify situation where there is a possibility of resurgence of disease when the antigenic preparation contains the organism in any form whatsoever. Expression of antigens as vaccines and of antibodies against antigens of pathogens in transgenic plants is a convenient and inexpensive source for various bacterial, viral, helminths, protozoan and autoimmune diseases with lower capital costs. This review describes various diseases along with the production of edible transgenic plant vaccines/proteins for the same. Thus, substituting and improvising conventional immunization methods.

Vitamin B12-mediated transport: a potential tool for tumor targeting of antineoplastic drugs and imaging agents.

The uptake of vitamin B12 (cyanocobalamin, Cbl/VB12) in mammalian cells is mediated by specific, high-affinity receptors for the vitamin B12-binding protein, transcobalamin II, which is expressed on the plasma membrane. The receptor for vitamin B12 is overexpressed on a number of human tumors, including cancers of the ovary, kidney, uterus, testis, brain, colon, lung, and myelocytic blood cells. Furthermore, the affinity of cyanocobalamin conjugates for cell surface transcobalamin II receptors seems to be high enough so that vitamin B12 derivatization with the cytotoxic agent or carriers bearing cytotoxic drugs allows the selective delivery of diagnostic and therapeutic agents to cancer cells. Thus, conjugates of vitamin B12 enter receptor-expressing cancer cells via receptor-mediated endocytosis, and targeting may be accomplished by multiple mechanisms, depending on the drug-delivery strategy. This review summarizes the applications of vitamin B12 as a targeting ligand and highlights the various methods being developed for delivery of therapeutic and imaging agents to cancer cells in vitro and in vivo. This review reflects the potentiality of vitamin B12 for tumor targeting of chemotherapeutic and diagnostic agents.

Novel molecular targets for antimalarial drug development.

Malaria with one million deaths and about 500 million new cases reported annually is a challenge to drug therapy and discovery. As current antimalarial therapeutics become increasingly ineffective because of parasitic resistance, there exists an urgent need to develop and pursue new therapeutic strategies. Antimalarial drug development can follow several strategies, ranging from minor modifications of existing agents to the design of novel agents that act against new targets. Recent advances in our knowledge of parasite biology as well as the availability of the genome sequence provide a wide range of novel targets for drug design. Several promising targets for drug intervention have been revealed in recent years. This review discusses novel molecular targets of the malaria parasite available to the drug discovery scientist.

QSAR analysis of 1,3-diaryl-4,5,6,7-tetrahydro-2H-isoindole derivatives as selective COX-2 inhibitors.

Quantitative structure-activity relationship (QSAR) analysis was performed on a series of 1,3-diaryl-4,5,6,7-tetrahydro-2H-isoindole for their cyclooxygenase-2 (COX-2) inhibition. QSAR investigations were based on Hansch's extra thermodynamic multi-parameter approach and receptor surface analysis (RSA). QSAR investigations reveal that steric and electrostatic interactions are primarily responsible for COX-2 enzyme-ligand interaction. QSAR model derived from Hansch analysis demonstrated that COX-2 inhibitory activity is correlated with sum of atomic polarizability (Apol), number of hydrogen-bond donor groups (HBD), energy of the highest occupied molecular orbital (HOMO), desolvation free energy for water (F(H(2)O)) and fraction of areas of molecular shadow in the XY and ZX planes over area of enclosing rectangle (Sxyf and Sxzf) with r ranges 0.870-0.904. The best model was obtained from RSA model having r = 0.940 with good predictive ability (predicted compounds in training set and test set within +/- 1.0 unit of pIC(50)) and can be used in designing better selective COX-2 inhibitors among the congeners in future.